*ANNA UNIVERSITY,CHENNAI*

*EC2151*ELECTRIC CIRCUITS AND ELECTRON DEVICES QUESTION BANK

**BE/BTECH SECOND SEMESTER**

**UNIT 1**

1. Define charge and current.

2. Define voltage and power.

3. Distinguish between ideal and practical voltage source.

4. Distinguish between ideal and practical current source.

5. Define resistivity.

6. What is known as Network?

7. State Ohms law.

8. State KVL and KCL.

9. What is voltage division formula?

10. What is current division formula?

11. What is the criterion to use mesh analysis?

12. What is the criterion to use nodal analysis?

13. State linearity.

14. State Superposition Theorem.

15. State Thevenins Theorem.

16. State Norton’s Theorem.

17. State Maximum Power transfer Theorem.

18. What are the limitations of Thevenins theorem?

19. What are the limitations of Norton’s theorem?

20. Give some applications of superposition theorem.

**UNIT II**

1. What is meant by sinusoidal steady state analysis?.

2. What is known as phasor diagram

3. Define RMS value

4. What is meant by form factor?

5. What is meant by peak factor?

6. What is the use of superposition theorem?

7. Draw simple RLC circuit.

8. Draw simple RL circuit

9. Draw simple RC circuit

10. Define power factor for RL, RC and RLC circuit

11. Draw the phasor diagram for R, L& C Circuits.

12. Draw the phasor diagram for RL and RC Circuits.

13. Draw the phasor diagram for RLC Circuit.

14. What is meant by complex circuit?

15. Define complex power.

16. Define: Q factor

17. What is single tuned circuit?.

18. What is double tuned circuit?

19. What are Parallel and series resonances?.

**UNIT III**

1. What is the difference between Intrinsic & extrinsic semiconductor?

2. Draw the energy band diagram for conductor, insulator and semiconductor?

3. Why silicon is always preferred than germanium?

4. What are the difference between N type & P type semiconductor? Give example?

5. What is Fermi Dirac distribution function?

6. What is Fermi level?

7. What are the difference between drift and diffusion current?

8. Write down the diode current equation?

9. What is mobility?

10. What is knee voltage?

11. What is the difference between diffusion and transition capacitance?

12. Draw the energy band structure of pn junction diode

13. What is diode storage and reverse recovery time?

14. What is peak inverse voltage?

15. Draw the VI characteristic of Zener diode?

16. What is the difference between avalanche and Zener breakdown?

17. What are the application of Zener diode?

18. Draw the energy band diagram of intrinsic semiconductor?

**UNIT IV**

1. Draw the symbol for PNP /NPN transistor?

2. What is transistor ?

3. What is rise time ,delay time,fall time?

4. What is pinch off voltage ? what is cutoff voltage?

5. Compare BJT and FET?

6. Compare FET and MOSFET/

7. What is q point or operating point ?

8. What is ac and dc load line?

9. What is thermal runaway?

10. What is heat sink?

11. What is stability factor?

12. Compare depletion and enhancement MOSFET?

13. Draw the symbol of n channel and p channel JFET ?

14. Draw the symbol of depletion and enhancement MOSFET?

15. Wht base of transistor is made thin?

16. Why emitter is heavily doped?

17. What is active/saturation/cutoff region?

18. What is early effect or base width modulation?

**UNIT V**

1. What is holding current?

2. What are the applications of SCR?

3. What is thyristor?Why it is called a Triggering device?

4. What is unidirectional and bidirectional Thyristor?Give example?

5. Draw the two transistor version of SCR?

6. Compare TRIAC and DIAC?

7. What are the application of TRIAC/DIAC?

8. What is UJT?

9. What is intrinsic stand off ration?

10. Compare LED and LCD?

11. What is photodiode /photo transistor?

12. What is optocoupler? What are its applications?

13. What is solar cell?

14. Explain field effect or twisted neumatic LCD?

15. Draw the characteristic of UJT and identify the negative resistance region?

16. Explain regenerative action of SCR?

17. What is photo voltic voltage of solarcell?

18. What are the materials used for the construction of LED?

19. Draw the structure of Smectic ,Nematic and cholestic LCD?

20. What is tunneling effect?

21. What are the application of tunnel diode?